General Characteristics

BM series

BM series consists of three phase, asynchronous brake motors totally enclosed fan cooled. BM series range starts from 56 up to 160frame size. The motor brakes in case of power supply failure. The brake torque remains the same in both directions of rotation and themotor brakes without shaft axial sliding. As standard the brake is DC voltage supply with a built-in rectifier fitted inside the terminal box.The rectifier is provided with over-voltage and radio frequencies emission protection devices. Two different types of rectifier wiring can bechosen according to two different brake intervention time. BM series is designed in order to have a braking action as quiet as possible. BM series motors tolerate a high overloading rate and arecapable to withstand overheating so to guarantee best reliability also under tough operating conditions. All MGM motors have been designed to be controlled by inverters. The motor winding insulation is class F, while class H is available onrequest. Motor construction type is totally enclosed externally cooled and IP54 enclosure (IP55 and IP56 available on request). Motors up to 132 frame size are fitted as standard with a hexagonal hole on the shaft at non drive end to allow manual rotation, even ifpower is off. On request, BM series motors can be provided with side manual brake release lever. The brake disc lining material is asbestosfree and the lining mixture is formulated to have a high friction coefficient and long lasting. BM series motor frame is made of die cast, light metal on motors up to 132 size and the terminal board box, provided with cable glandsand plugs, is positioned 180 ° above the motor support feet. The frame is made of cast iron starting from 160 frame size and the terminalbox is located on the right side (drive-end view). Shields and flanges are made of aluminium on motors up to 90 frame size, and of castiron on motors of 100 frame size and above. On IM B3 mounting (foot mounted) feet are frame integrated (they are not simply attachedto the frame) as standard and it makes the motor very sturdy. This feature is very important for those applications where the motor ismuch stressed during the starts and stops. BM series main features are the low braking noise, gradual acceleration during the motorstart and stop and reduced overall dimensions.
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